New Avenues to Heavy Right-handed Neutrinos with Pair Production at Hadronic Colliders

TL;DR

This paper investigates the potential to discover heavy right-handed neutrinos through pair production at current and future hadronic colliders, proposing new search strategies based on multiple decay signatures.

Contribution

It introduces novel collider signatures and analysis methods for detecting TeV-scale right-handed neutrinos via pair production, which has been less explored in prior research.

Findings

Heavy neutrino pair production can be detected at 14 TeV and 100 TeV colliders.

Multiple decay channels provide complementary discovery avenues.

TeV-scale right-handed neutrinos are within reach of future collider experiments.

Abstract

In many models incorporating the type-I seesaw mechanism, the right-handed neutrino ($N$) couples to heavy vector/scalar bosons and thereby has resonant pair production. It barely receives attention thus far, however, it may provide the best avenue to probe TeV scale $N$ without requiring anomalously large mixing between $N$ and the active neutrino $\nu_L$. In this paper we explore the discovery prospects of (mainly heavy) $N$ pair production at the 14 TeV LHC and future 100 TeV $pp$ collider, based on the three signatures: 1) trilepton from $ N(\rightarrow \ell W_\ell)N(\rightarrow \ell W_h)$ with $W_{\ell/h}$ the leptonically/hadronically decaying $W$; 2) boosted di-Higgs boson plus MET from $N(\rightarrow \nu_L h)N(\rightarrow \nu_L h)$; 3) a single boosted Higgs with leptons and MET from $N(\rightarrow \ell W_\ell)N(\rightarrow \nu_L h)$. At the 100 TeV collider, we also consider the situation when the Higgs boson is over boosted thus losing its jet substructure. Interpreting our tentative results in the benchmark model, the local $B-L$ model, we find that the (multi-) TeV scale $N$ can be probed at the (100) 14 TeV colliders.